So, for the pregnancy to grow, the uterine arteries should be adequate, having enough amount of blood going through them. Now the uterine arteries are the two main, supplies from the right and from the left through which the blood reaches the uterus. If there is any decrease in the supply from the blood it causes growth retardation, obviously because the baby’s nutrition is blood.
So we have a lot of parameters by which we assess the blood flow in the uterine arteries, right from the first trimester. At around 12 to 13 weeks, we look at the vessels for the first time and if the resistance is more, that means less blood is going through.
We anticipate that this pregnancy will end up in some bit of growth retardation and we could start some intervention at that time. Then at 23 weeks, we can get a more definite clue and if there is low flow in the uterine arteries at that time, there’s a higher risk of pregnancy-induced hypertension or preeclampsia toxemia, which are serious conditions in later pregnancy.
So it is a predictive test. We can figure out whether this pregnancy is going to have problems based on how much blood flow is going through the vessels.